| 摘要 |
A device (500) has a first, lower sub housing (112), a second, upper sub housing (102), and an extensible joint (110) connecting the lower sub housing (112) to the upper sub housing (102). A pressure equalization chamber (502) is attached to the upper sub housing (102) and demarcates an inner zone (508) including an internal mechanism of the extensible joint, and an outer zone (510) open to well bore fluids and pressure. A fluid barrier (506) moves within the pressure equalization chamber (502) in response to changes in well bore pressure to alter a volume of the inner zone (508) to equalize a pressure of the inner zone. |
